Hexagon Circumscribing A Circle Area Calculation Explained

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Hey guys! Today, we're diving into a fascinating geometry problem that involves a regular hexagon circumscribing a circle. This means the hexagon is drawn around the circle, touching it at each of its sides. We're given that the area of the circle is 144Ï€ square centimeters, and our mission, should we choose to accept it, is to find the area of the region enclosed between the hexagon and the circle. Sounds intriguing, right? Buckle up, because we're about to embark on a mathematical adventure!

Cracking the Code: Understanding the Hexagon and Circle Relationship

Before we jump into calculations, let's get a solid grasp of the relationship between the hexagon and the circle. Imagine a regular hexagon perfectly hugging a circle from the outside. Each side of the hexagon is tangent to the circle, meaning it touches the circle at exactly one point. Now, if we draw lines from the center of the circle to each vertex (corner) of the hexagon, we'll notice something cool: we've divided the hexagon into six identical equilateral triangles! This is a crucial observation because it links the hexagon's geometry to the circle's radius. The radius of the inscribed circle is also the height (or apothem) of each of these equilateral triangles.

To really understand this, let's break it down further. Think about one of those equilateral triangles. The center of the circle is the point where the three angle bisectors of the triangle meet. This point is also the centroid (the balancing point) and the circumcenter (the center of the circumscribed circle) of the triangle. The radius of our inscribed circle is the distance from this central point to the midpoint of any side of the equilateral triangle. This distance is also the apothem of the hexagon. Now, the area of the circle, which we know is 144π sq. cm, holds the key to unlocking the dimensions of both the circle and the hexagon. Remember the formula for the area of a circle? It's πr², where 'r' is the radius. So, by using this formula and some clever deductions, we can find the radius of the circle, which will then help us determine the side length of the hexagon and its area. This is where the magic of geometry truly shines – connecting seemingly disparate pieces of information to solve a puzzle!

Furthermore, visualizing this relationship is incredibly helpful. Try sketching a diagram of the hexagon and the circle. Draw the lines from the center to the vertices of the hexagon, and then draw the radius to the midpoint of one of the sides. This visual representation will solidify your understanding of how the circle's radius is related to the hexagon's sides and area. Remember, in geometry, a clear picture can often be worth a thousand calculations!

Unraveling the Mystery: Calculating the Radius and Side Length

Let's start by using the given information about the circle's area to find its radius. We know the area of the circle is 144π sq. cm, and the formula for the area of a circle is πr². So, we can set up the equation:

πr² = 144π

To solve for 'r', we can divide both sides of the equation by π:

r² = 144

Now, we take the square root of both sides to find the radius:

r = √144 = 12 cm

Awesome! We've found that the radius of the circle is 12 cm. Now, let's use this information to figure out the side length of the hexagon. Remember those equilateral triangles we talked about earlier? The radius of the circle is the height (apothem) of each of these triangles. In an equilateral triangle, the height divides the triangle into two 30-60-90 right triangles. The sides of a 30-60-90 triangle are in the ratio 1:√3:2. The height (opposite the 60-degree angle) corresponds to the side with length √3, and the side opposite the 30-degree angle is half the length of the hypotenuse. The hypotenuse is also the side of the equilateral triangle (and the hexagon!).

Since the radius (height) is 12 cm, we can set up a proportion:

√3 * x = 12

Where 'x' is the length of the side opposite the 30-degree angle. Solving for 'x', we get:

x = 12 / √3

To rationalize the denominator, we multiply the numerator and denominator by √3:

x = (12√3) / 3 = 4√3 cm

Now, remember that 'x' is half the side length of the equilateral triangle (and the hexagon). So, to find the full side length ('s'), we multiply 'x' by 2:

s = 2 * 4√3 = 8√3 cm

Excellent! We've successfully calculated the side length of the hexagon to be 8√3 cm. This is a major step forward in solving our problem. We now have the radius of the circle and the side length of the hexagon, which are the key ingredients we need to find the areas and ultimately the area between them. See how all the pieces are starting to fit together? That's the beauty of problem-solving in mathematics – each step builds upon the previous one, leading you closer to the final answer.

Putting It All Together: Calculating the Areas and the Final Answer

Now that we know the radius of the circle (12 cm) and the side length of the hexagon (8√3 cm), we can calculate their respective areas. Let's start with the area of the hexagon. Remember that the hexagon is made up of six equilateral triangles. The area of an equilateral triangle is given by the formula (√3 / 4) * s², where 's' is the side length. So, the area of one equilateral triangle in our hexagon is:

Area of one triangle = (√3 / 4) * (8√3)² = (√3 / 4) * (64 * 3) = (√3 / 4) * 192 = 48√3 sq. cm

Since there are six triangles, the total area of the hexagon is:

Area of hexagon = 6 * 48√3 = 288√3 sq. cm

Next, let's calculate the area of the circle, which we already know is 144Ï€ sq. cm (it was given in the problem!). However, let's double-check our work using the radius we calculated:

Area of circle = πr² = π * (12)² = π * 144 = 144π sq. cm

Great! It matches the given information, which confirms our calculations so far. Now, for the final step: finding the area bounded by the hexagon and the circle. This is simply the difference between the area of the hexagon and the area of the circle:

Area bounded = Area of hexagon - Area of circle

Area bounded = 288√3 - 144π sq. cm

This is our final answer! We've successfully found the area of the region enclosed between the hexagon and the circle. It's a bit of a complex expression, but it accurately represents the area we were looking for. We can also approximate this value using the values of √3 and π:

Area bounded ≈ 288 * 1.732 - 144 * 3.1416 ≈ 498.816 - 452.3904 ≈ 46.4256 sq. cm

So, the area bounded by the hexagon and the circle is approximately 46.43 square centimeters. We made it, guys! We took a challenging geometry problem, broke it down into smaller, manageable steps, and solved it. This is the power of understanding the relationships between geometric figures and applying the right formulas and techniques. Remember, practice makes perfect, so keep exploring and tackling those geometry problems!

Key Takeaways and Real-World Connections

This problem wasn't just about finding an area; it was about understanding the intricate relationships between geometric shapes. We saw how a hexagon circumscribing a circle can be dissected into equilateral triangles, and how the circle's radius acts as the apothem of these triangles. This connection allowed us to bridge the gap between the circle's area and the hexagon's dimensions. Moreover, we honed our skills in working with 30-60-90 triangles and applying the area formulas for circles and equilateral triangles. These are fundamental concepts in geometry that pop up in various contexts.

But geometry isn't confined to textbooks and exams. It's all around us! Think about architecture, engineering, and even nature. Hexagons, for instance, are incredibly efficient shapes found in honeycombs and snowflakes. Circles are ubiquitous in wheels, gears, and the orbits of planets. Understanding the properties of these shapes is crucial in designing structures, machines, and understanding natural phenomena. The principles we used to solve this problem – breaking down complex shapes into simpler ones, identifying relationships, and applying formulas – are the same principles that engineers and architects use every day to create the world around us. So, by mastering geometry, we're not just learning about shapes and areas; we're gaining a deeper understanding of the world and the principles that govern it.

Furthermore, the problem-solving process we went through is a valuable skill in itself. We started with a complex problem, identified the key pieces of information, developed a plan of attack, executed the plan step-by-step, and arrived at a solution. This is a transferable skill that can be applied to various challenges in life, whether it's planning a project, making a decision, or tackling a tough problem at work. So, keep practicing those geometry problems, not just for the sake of math, but for the sake of honing your problem-solving skills, which are essential for success in any field. And remember, the more you explore the world of geometry, the more you'll appreciate its beauty and its power to explain the world around us.